ABACUS (23 page)

AP nodded without saying anything.

“How about you? What was your favorite trip?”

“Probably the first one. I really connected with Arthur, like you with Talking Cloud. I was really sorry when we had to leave.”

“I was sorry to leave Egypt too. I had a good thing going there!”

“So, are you ready for another trip?”

“What, right now?” asked Kate.

“No. But sometime in the next few weeks.”

“What've you got in mind?”

“There are so many interesting times and places. After ‘Camelot' I'd like to see some real castles—with armor and jousting. Maybe the next trip should be to the Mesozoic, to see living dinosaurs.”

“What about Snakebite?”

“He's just the price we have to pay for all the fabulous things we see. Besides,” AP broke into a grin, “he may not be so bad when you get to know him!”

Kate pulled the pillow from his bed and hit him with it.

* * *

On the other side of the world, and forty-seven years into the future, Robert Drew was developing an apparatus to detect the abacus when it was not in use. The device he'd built for tracking it during activation—first tested in Medieval England—had taken over two years to perfect. He hoped the new equipment would be ready much sooner.

Fu
rther Reading

For Young People

Medieval Britain and the Arthurian legend

Although many books have been written about King Arthur, most are fiction and are not included. The ancient Britons, unlike the ancient Egyptians, left few written accounts of their times which is why we have so little reliable information about them.

The Discovery of King Arthur.
Geoffrey Ashe, 1985. Henry Holt, New York, 224 pp.

Everyday Life in Roman and Anglo-Saxon times
. Marjorie and C.H.B. Quennell, 1959. B.T. Batsford, London, 236 pp.

Plains Indians and Custer

Atlas of Indians
. Gilbert Legay, 1995. Barron's Educational Series, Hauppauge, New York, 95 pp.

Indians of the Plains
. Elaine Andrews, 1992. Facts on File, New York, 96 pp.

Plains Indians
. Fiona MacDonald, 1993. Barron's Educational Series, Hauppauge, New York, 56 pp.

The Plains Indians
. Colin F. Taylor, 1994. Crescent Books, New York, 256 pp.

Ancient Egypt

Egypt
(Ancient World Series). Jane Shuter, 1999. Steck-Vaughn Company, Austin, Texas, 63 pp.

Egyptian Mummies: People from the Past
. Delia Pemberton, 2001. Harcourt, San Diego, 48 pp.

Life in Ancient Egypt
. Thomas Streissguth, 2001. Lucent Books, San Diego, 93 pp.

Lost Civilizations: The Ancient Egyptians
. Allison Lassieur, 2001. Lucent Books, San Diego, 96 pp.

People Who Made History in Ancient Egypt
. Jane Shuter, 2001. Steck-Vaughn Company, Austin, Texas, 48 pp.

Pharaohs and Priests
. Jane Shuter, 1999. Heinemann Library, Des Plaines, Illinois, 32 pp.

For Parents and Teachers

Medieval Britain and the Arthurian legend

See
Further reading
—
for Young People
above.

Plains Indians and Custer

Atlas of the North American Indian
. Carl Waldman, 2000. Facts on File, New York,

385 pp.

Bury my Heart at Wounded Knee
. Dee Brown, 1972. Bantam Books, New York, 458 pp.

Black Elk Speaks: Being the Life Story of a Holy Man of the Oglala Sioux
. John G. Neihardt (editor) 1979 (first published 1932). University of Nebraska Press, Lincoln, Nebraska, 298 pp.

Crazy Horse and Custer
. Stephen E. Ambrose, 1996. Anchor Books, New York, 527 pp.

Everyday Life of the North American Indian
. J. Manchip White, 1979. Dover Publications, Mineola, New York, 256 pp.

The Indians of the Great Plains
. Norman Bancroft-Hunt, 1981. Orbis Publishing, London, 128 pp.

Indians of the Plains
. Robert H. Lowie, 1982 (first published 1954). University of Nebraska Press, Lincoln, Nebraska, 222 pp.

My People the Sioux
. Luther Standing Bear, 2006 (first published 1928). University of Nebraska Press, Lincoln, Nebraska, 288 pp.

The Story of the Little Big Horn
. W. A. Graham, 1988 (first published 1926). University of Nebraska Press, Lincoln, Nebraska, 178 pp.

Ancient Egypt

Chronicles of the Pharaohs: The Reign-By-Reign Record of the Rulers and Dynasties of Ancient Egypt
. Peter A. Clayton, 1994. Thames & Hudson,
London, 224 pp.

The Complete Temples of Ancient Egypt.
Richard H. Wilkinson, 2000. Thames & Hudson, London, 256 pp.

Egypt and the Egyptians
. Douglas J. Brewer & Emily Teeter, 1999. Cambridge University Press, Cambridge, 218 pp.

Egyptian Mummies: Unraveling the Secrets of an Ancient Art
. Bob Briar, 1994. William Morrow, New York, 352 pp.

Everyday Life in Egypt in the Days of Ramesses the Great
. Pierre Montet, 1981 (first published 1958). University of Pennsylvania Press, Philadelphia, 365 pp.

Go
ds of Ancient Egypt
. Barbara Waterson, 1996. Sutton Publishing, Stroud, Gloucestershire, 227 pp.

The Hieroglyphs of Ancient Egypt
. Aidan Dodson, 2001. New Holland Publishers, London,

144 pp.

The Horizon Book of Daily Life in Ancient Egypt
. Lionel Casson, 1975. American Heritage, New York, 128 pp.

Introducing Egyptian Hieroglyphs
. Barbara Watterson, 1993. Scottish Academic Press, Edinburgh, 152 pp.

Kings and Queens of Ancient Egypt
. Various contributors, portraits by Winifred Brunton, 1924. Hodder and Stoughton, London, 160 pp.

Mummies: Death and Life in Ancient Egypt
. James Hamilton-Paterson and Carol Andrews, 1978. Collins, London, in association with British Museum Publications Ltd., London, 224 pp.

The Priests of Ancient Egypt
. New Edition. Serge Sauneron, 2000. Cornell University Press, Ithaca, New York, 215 pp.

Notes

These notes explain some of the facts in the story, and give some background information about the real historical events and how they compare to what Kate and AP saw.

[1]
Fishermen in medieval England
used a rod and line, without a reel. Claudius Aelianus, a Roman writer of this period, says feathers were attached to the iron hook to lure the fish, instead of bait.

[2]
A quill pen
is made from the wing feather of a large bird, like a chicken, by cutting off the end at an angle. When the hollow quill is dipped in ink, some of the ink runs up inside the quill (by a process called capillary action), and the quill acts as a reservoir.

[3] A
league
, a unit of distance used in Roman times, was about 1.5 miles (just over 2 kilometers).

[4]
Parchment
, made from the inside layer of sheep skin, was used for writing upon long before paper was developed.

[5]
Enchanter's
nightshade (Circaea lutetiana)—not to be mistaken for deadly nightshade (Atropa belladonna), which is a poisonous plant—was once used for cleaning wounds.

[6]
To find the North Star
(Polaris), find the Big Dipper (or Plough). Draw a line through last two stars at the “cup” end. Polaris lies along this line, about one Big-Dipper-length away. You can find a star map online using the keywords “North Star” and “Big Dipper.”

[7] Although hook and line fishing was used by Indians,
spearfishing
was more common.

[8]
General Crook
had 260 Indians under his command, mostly Crows and Shoshones.

[9]
Black Hawk
, the warrior who brought word from Sitting Bull and Crazy Horse, is a fictional character. Indians at that time would have called the Little Bighorn by its Indian name:
Greasy Grass
.

[10] AP and Kate would have been very lucky to be picked up on the
Bozeman
Trail because it was not being used by settlers until shortly after the Battle of the Little Bighorn.

[11] While
General Crook
was heading north along the Rosebud River to find the Sioux, Crazy Horse and his warriors were heading south to find the soldiers. Crazy Horse spotted them on the morning of June 17. He took them by surprise while Crook and his soldiers were letting their horses graze. Crook took such a beating that he retreated back to his fort. (See Crazy Horse and Custer, pp. 420–4.)

[12] About a week before the Battle of the Little Bighorn, Custer ordered that all of the
sabers
be crated, so it is unlikely he wore one on June 22.

[13] Bloody Knife, like the other scouts, did think there were
too many Sioux
for the Army to handle.

[14]
Custer
would have addressed his men sometime before the battle, but there is no record that he did so before setting out on June 22.

[15] Custer usually had the band playing, and their most popular tune was “
Garryowen
.” However, Custer left the band behind sometime around June 16.

[16] The comment by
Gibbon
as Custer rode off is in his own words. (See Crazy Horse and Custer, pp. 427–8.)

[17] Bloody Knife really did say that
Custer couldn't hit a tent from the inside!
(See
Crazy Horse and Custer
, pp. 365, 378.)

[18] There was a real conversation between two officers after the Council of War meeting on June 22, 1876, where one said he thought
Custer was going to be killed
. (See Crazy Horse and Custer, p. 428.)

[19]
Sitting Bull
did have a vision of
soldiers falling
with their heads down.

[20]
Knife
warned Custer
there were more Sioux than they had bullets for, but it is not known whether he suggested they wait until Gibbon arrived.

[21] Custer did shout out,
“We've caught them napping,”
but not until his detachment was in position at the north end of the Indian camp.

[22] Custer sent
Reno's orders
by messenger because Reno was already some distance away. Custer said his detachment would support him, but instead of following Reno into the attack, Custer took his men to the north end of the camp.

[23] The 20-minute length estimate for
Custer's battle
is from Crazy Horse and Custer, p. 443.

[24] Reno almost lost his nerve at the start of the fighting when
Bloody Knife was shot dead
, and his brain splattered across the Major's face.

[25]
Natron
, which the ancient Egyptians called netjeryt, is sodium carbonate.

[26] Ramesses II did have a vizier named
Nehy
, but the stories told here of his death and later burial are fictitious.

[27] AP knew that
steel was better than iron
for making a permanent magnet, but he also knew that steel had not yet been invented!

[28] AP calls each of the pots with copper and iron in them a battery, but that's not quite right. The individual containers with their copper and iron electrodes, should have been called
cells
. When cells are joined together they form a battery (of cells).

[29] AP had to trade goods for their journey down the Nile because
ancient Egyptians did not use money
.

How to Repeat the Experiments in the Book

If possible, do these experiments with a partner so you can talk about them and help each other. You MUST have an adult helper for some experiments.

Make soap (Chapter 5)

Making soap is easy but it involves boiling a liquid which soon becomes caustic. This activity therefore requires adult supervision and great care. For these reasons the instructions will not be included here. This would be an ideal project to do at school. Visit our website
www.abacusAdventure.com
to see how to get the instructions.

Use a small hole to improve vision (Chapter 8)

This simple experiment only works for people who have to use glasses to read. So, if you don't use reading glasses, find someone who does: maybe an older family member like a grandparent. This person will be the subject of your experiment.

You'll need:

a square piece of paper, 2 × 2 inches (5 × 5 cm)

a needle or pin

a subject: someone who needs reading glasses

1. Ask your subject to try reading something, like a newspaper or the small print on a cereal box, without wearing glasses. Do this indoors, without a reading lamp. The print will look blurry and your subject will probably be unable to read it.

2. Use the pin to make a small hole (about 1 mm in diameter) in the piece of paper. Ask your subject to hold the paper up close to one eye, so he or she can see through the hole. If your subject can't see properly, try making the hole a little bigger. The print should no longer look fuzzy, and your subject should be able to read it.

Note: Can your subject read small print without wearing glasses outdoors in bright sunlight (or indoors, using a bright lamp)? The answer is probably yes. This is because the pupil—the black hole in the center of the eye—gets smaller, or contracts, when bright light falls on it. So reading outdoors in bright sunlight is just like reading through a pinhole. Squinting has the same effect.

Make a pinhole camera (Chapter 29)

You'll need:

an adult helper

an empty tin can, open at one end

a hammer and a nail

wax paper or a white plastic bag

an elastic band

a piece of thick, dark cloth large enough to cover your head

a small piece of aluminum foil (the size of a postage stamp)

Scotch tape

a needle or pin

a sharp pencil or round toothpick

1. Ask your adult helper to punch a small hole in the center of the bottom of the can using a hammer and nail. Prick a hole in the center of the aluminum foil. Tape the foil to the bottom of the can, lining up the pinprick with the hole. Hold it up to the light to check the alignment.

2. Using a sharp pencil or round toothpick, enlarge the hole in the foil to a diameter of 1/16 inch (1.5 mm). Use a twisting action while you do this to make sure the hole is round.

3. Cut off a piece of wax paper or plastic just large enough to cover the open end of the can, with an overlap of about 1 inch (2 cm). Secure the paper or plastic with the elastic band, pulling it tight like a drum. This is the screen of your pinhole camera.

4. Go outside, preferably on a bright day, and point the pinhole toward a distant object, like a tree. Place the cloth over your head and drape it around the screen end of your pinhole camera. Make sure the cloth cuts out most of the light but doesn't cover the screen. Your face should be about 9 inches (23 cm) away from the screen. Focus your eyes on the screen and move the camera from side to side. You should see an upside-down image of the object on the screen.

Generate electricity with a lemon (Chapter 31)

You'll need:

a lemon

a knife

a copper coin (1 cent or 1P or 2P)

a paper clip (the silver-colored iron kind, not the gold-colored brass or colored kinds)

1. Wash the coin thoroughly—you're going to lick it!

2. Use the knife to make two small slits in the skin of the lemon, ¼ inch (5 mm) apart.

3. Push the coin into one of the slits so that only a few millimeters protrude. Repeat for the paper clip.

4. Touch your tongue across the coin and the paper clip. You should feel the metal-taste sensation of the electricity that this simple cell generates.

Magnetize a sewing needle, using a AA battery (Chapter 31)

You'll need:

an old AA battery (don't use a new battery!)

6 feet (2 m) of insulated wire (You can buy reels of wire from an electronics shop. They come in different colors according to thickness. The green one works well.)

sandpaper or an emery board

2 large darning needles

Scotch tape

a length of thread about 1 foot (30 cm) long

1. Leaving 2 inches (5 cm) of wire free at the end, wrap the wire around the needle, starting 1/4 inch (1/2 cm) from one end. Make sure each coil touches its neighbor. The easiest way to do this is to wind 4 coils at a time—spreading them out along the needle—and then push them together so they touch. Don't wrap the wire too tightly because you need to remove the needle! When you are 1/4 inch (1/2 cm) from the other end of the needle, continue wrapping over the top of the first layer of wire. This time, instead of making each coil touch its neighbor, just get them as close as you can. Continue until you have 6 or 7 layers of wire. Snip off the wire, leaving 2 inches (5 cm) free at the end.

2. Strip the colored insulation from the two ends, over a length of about 1 inch (2 cm). Do this by rubbing the wire with sandpaper or an emery board. Otherwise, get an adult to scrape the wire with a knife. Hold the two bared wires to the two terminals of the battery. Warning: The coil will get warm, and if the battery is too fresh the coil will get too hot to touch. If that happens, disconnect and allow the coil to cool down before reconnecting.

3. Try picking up a paper clip while the battery is still connected—you have made an electromagnet. When you disconnect one of the wires, the paper clip falls.

4. Using tape, connect the coil to the battery and leave for 1 minute to permanently magnetize the needle. If the coil gets too hot to touch, disconnect one of the wires and allow it to cool before reconnecting. Disconnect the coil from the battery, and then remove the needle from the coil. Try picking up a paper clip—the needle is probably too weakly magnetized to do this.

5. Using a small piece of tape, attach the needle to one end of the thread so it hangs horizontally. Attach the other end to the edge of a table or bookshelf so the needle swings freely. Important: Choose a place with no metal nearby! When the needle stops swinging, make a note of its direction. Gently prod one end of the needle. See if it returns to the same position when it stops swinging (it should be pointing north and south).

6. Make a second magnet by slipping a second needle into the coil and connecting to the battery for 1 minute. Disconnect the battery and remove the needle from the coil. Slowly bring one end of the second magnet toward one end of the first magnet. The suspended magnet will either be attracted or repelled. If you switch ends and try again you'll get the opposite reaction: like poles repel, opposite poles attract.

Make your own battery and use it to magnetize a needle (Chapter 31)

You'll actually be making just one cell of a battery. If you made two or more such cells and joined them together, this would be called a battery (of cells).

You'll need:

an adult helper

25 feet (8 m) of steel strapping (not galvanized)

pliers

2 copper dish scourers

a large bottle of white vinegar (1 gallon or 4 L will be plenty)

1 plastic bucket

2 feet (60 cm) of twin-flex wire (speaker wire from a radio shop works well)

the wire coil from the previous experiment

2 large darning needles (don't use one you've already magnetized!)

some paper towel

a length of thread about 1 foot (30 cm) long

Scotch tape

an old knife

Note: Strapping is a narrow strip of metal, ½–¾ inch wide (15-20 mm) perforated with holes, which is used in plumbing for securing pipes. You can find it in hardware stores.

1. Join the two dish scourers together—side by side—by pulling out loops of copper and twisting them tightly together.

2. Carefully remove the coil of steel strapping from its box, making sure it doesn't unravel.

3. Separate the two strands of twin-flex wire at either end, so that each free end is about 4 inches (10 cm) long. Ask your helper to strip 1 inch (2 cm) of the plastic insulation from each strand, at each end, using the knife.

4. Connect one of the bared wires to the outer end of the steel coil. Connect its neighbor to one end of the joined scourers.

5. Position the steel coil and copper scourers side by side on the bottom of the bucket. Loosely wrap the scourers in a sheet of paper towel so they don't touch the coil. Make sure the two connecting wires are separated by paper towel too. Warning: if the copper and steel—or their connecting wires—touch, your battery cell will not work. Drape the rest of the twin-flex wire over the side of the bucket.

6. Carefully slip one of the needles through the center of the wire coil from the previous experiment so that most of it is covered by the coil. Connect each end of the coil to one of the two free ends of the twin-flex wire. Do this by wrapping each one tightly around the bared wire. Important: if you don't make good contacts between the wires, your needle will not be magnetized.

7. Ask your helper to pour vinegar into the bucket so it covers the top of the copper scourers.
Warning:
Immediately wash off any splashes—vinegar can damage your clothes. Using a pencil, jiggle the steel coil to remove any air bubbles. Leave the wire coil connected overnight.

8. Disconnect the coil and remove the needle. Suspend the needle by the thread so that it swings freely, as in the previous experiment. Notice the direction in which it settles. Check to see if it returns to the same position after prodding one of the ends.

9. Add about 1 pint (1/2 L) of fresh vinegar and then magnetize a second needle, the same way as before. Keep the coil connected for about 24 hours. Holding the second magnetized needle, use it to attract and then repel, one end of the suspended one, as in the previous experiment.

END